Augustin-Jean Fresnel
Encyclopedia
Augustin-Jean Fresnel was a French
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 engineer who contributed significantly to the establishment of the theory of wave optics
Wave
In physics, a wave is a disturbance that travels through space and time, accompanied by the transfer of energy.Waves travel and the wave motion transfers energy from one point to another, often with no permanent displacement of the particles of the medium—that is, with little or no associated mass...

. Fresnel studied the behaviour of light both theoretically and experimentally.

He is perhaps best known as the inventor of the Fresnel lens
Fresnel lens
A Fresnel lens is a type of lens originally developed by French physicist Augustin-Jean Fresnel for lighthouses.The design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional design...

, first adopted in lighthouse
Lighthouse
A lighthouse is a tower, building, or other type of structure designed to emit light from a system of lamps and lenses or, in older times, from a fire, and used as an aid to navigation for maritime pilots at sea or on inland waterways....

s while he was a French commissioner of lighthouses, and found in many applications today.

Biography

Fresnel was the son of an architect, born at Broglie
Broglie, Eure
Broglie is a commune in the Eure department in Haute-Normandie in northern France.-Population:-References:*...

 (Eure
Eure
Eure is a department in the north of France named after the river Eure.- History :Eure is one of the original 83 departments created during the French Revolution on 4 March 1790...

). His early progress in learning was slow, and he still could not read when he was eight years old. At thirteen he entered the École Centrale in Caen
Caen
Caen is a commune in northwestern France. It is the prefecture of the Calvados department and the capital of the Basse-Normandie region. It is located inland from the English Channel....

, and at sixteen and a half the École Polytechnique
École Polytechnique
The École Polytechnique is a state-run institution of higher education and research in Palaiseau, Essonne, France, near Paris. Polytechnique is renowned for its four year undergraduate/graduate Master's program...

, where he acquitted himself with distinction. From there he went to the École des Ponts et Chaussées
École Nationale des Ponts et Chaussées
Founded in 1747, the École nationale des ponts et chaussées , often referred to as les Ponts, is the world's oldest civil engineering school...

. He served as an engineer successively in the departments of Vendée
Vendée
The Vendée is a department in the Pays-de-la-Loire region in west central France, on the Atlantic Ocean. The name Vendée is taken from the Vendée river which runs through the south-eastern part of the department.-History:...

, Drôme
Drôme
Drôme , a department in southeastern France, takes its name from the Drôme River.-History:The French National Constituent Assembly set up Drôme as one of the original 83 departments of France on March 4, 1790, during the French Revolution...

 and Ille-et-Vilaine
Ille-et-Vilaine
Ille-et-Vilaine is a department of France, located in the region of Brittany in the northwest of the country.- History :Ille-et-Vilaine is one of the original 83 departments created during the French Revolution on March 4, 1790...

; but having supported the Bourbons in 1814 he lost his appointment on Napoleon's
Napoleon I of France
Napoleon Bonaparte was a French military and political leader during the latter stages of the French Revolution.As Napoleon I, he was Emperor of the French from 1804 to 1815...

 return to power.

In 1815 on the second restoration of the monarchy he obtained a post as engineer in Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

, where he spent much of his life from that time onwards. He appears to have begun his research in optics around 1814 when he prepared a paper on the aberration of light
Aberration of light
The aberration of light is an astronomical phenomenon which produces an apparent motion of celestial objects about their real locations...

, although it was never published. In 1818 he wrote a memoir on diffraction
Diffraction
Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Italian scientist Francesco Maria Grimaldi coined the word "diffraction" and was the first to record accurate observations of the phenomenon in 1665...

 for which he received the prize of the Académie des Sciences
French Academy of Sciences
The French Academy of Sciences is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research...

 at Paris in the ensuing year. He was the first to construct a special type of lens, now called a Fresnel lens
Fresnel lens
A Fresnel lens is a type of lens originally developed by French physicist Augustin-Jean Fresnel for lighthouses.The design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional design...

, as a substitute for mirrors in lighthouses. In 1819 he was nominated to be a commissioner of lighthouses. In 1823 he was unanimously elected a member of the academy, and in 1825 he became a member of the Royal Society of London. In 1827, the time of his last illness, the Royal Society of London awarded him the Rumford Medal
Rumford Medal
The Rumford Medal is awarded by the Royal Society every alternating year for "an outstandingly important recent discovery in the field of thermal or optical properties of matter made by a scientist working in Europe". First awarded in 1800, it was created after a 1796 donation of $5000 by the...

.

Fresnel died of tuberculosis
Tuberculosis
Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...

 at Ville-d'Avray
Ville-d'Avray
Ville-d'Avray is a commune in the western suburbs of Paris, France. It is located from the center of Paris. The commune is served by the Boulogne-Billancourt prefecture, of the Hauts-de-Seine department.-Transport:...

, near Paris.

He received only scant public recognition during his lifetime for his labours in the cause of optical science. Some of his papers were not printed by the Académie des Sciences until many years after his death. But as he wrote to Young in 1824: in himself "that sensibility, or that vanity, which people call love of glory" had been blunted. "All the compliments," he says, "that I have received from Arago
François Arago
François Jean Dominique Arago , known simply as François Arago , was a French mathematician, physicist, astronomer and politician.-Early life and work:...

, Laplace and Biot
Jean-Baptiste Biot
Jean-Baptiste Biot was a French physicist, astronomer, and mathematician who established the reality of meteorites, made an early balloon flight, and studied the polarization of light.- Biography :...

 never gave me so much pleasure as the discovery of a theoretic truth, or the confirmation of a calculation by experiment".

His name is one of the 72 names inscribed on the Eiffel Tower.

Research

His discoveries and mathematical deductions, building on experimental work by Thomas Young
Thomas Young (scientist)
Thomas Young was an English polymath. He is famous for having partly deciphered Egyptian hieroglyphics before Jean-François Champollion eventually expanded on his work...

, extended the wave theory of light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 to a large class of optical phenomena
Optical phenomenon
An optical phenomenon is any observable event that results from the interaction of light and matter. See also list of optical topics and optics. A mirage is an example of an optical phenomenon....

. In 1817, Young had proposed a small transverse component to light, while yet retaining a far larger longitudinal component. Fresnel, by the year 1821, was able to show via mathematical methods that polarization could be explained only if light was entirely transverse, with no longitudinal vibration whatsoever.

He proposed the aether drag hypothesis
Aether drag hypothesis
In the 19th century, the theory of the luminiferous aether as the hypothetical medium for the propagation of light was widely discussed. An important part of this discussion was the question concerning the state of motion of Earth with respect to this medium. The aether drag hypothesis dealt with...

 to explain a lack of variation in astronomical observations.

His use of two plane mirrors of metal, forming with each other an angle of nearly 180°, allowed him to avoid the diffraction effects caused (by the apertures) in the experiment of F. M. Grimaldi
Francesco Maria Grimaldi
Francesco Maria Grimaldi was an Italian Jesuit priest, mathematician and physicist who taught at the Jesuit college in Bologna....

 on interference. This allowed him to conclusively account for the phenomenon of interference in accordance with the wave theory.

With François Arago
François Arago
François Jean Dominique Arago , known simply as François Arago , was a French mathematician, physicist, astronomer and politician.-Early life and work:...

 he studied the laws of the interference of polarized rays. He obtained circularly polarized light by means of a rhombus of glass, known as a Fresnel rhomb
Fresnel rhomb
A Fresnel rhomb is a prism-like device designed in 1817 by Augustin-Jean Fresnel for changing the polarization of light waves to be circularly polarized. Though the result is similar to that of using a wave plate, the rhomb does not depend on birefringent properties of the material...

, having obtuse angles of 126° and acute angles of 54°.

See also

  • Fizeau experiment
    Fizeau experiment
    The Fizeau experiment was carried out by Hippolyte Fizeau in 1851 to measure the relative speeds of light in moving water. Albert Einstein later pointed out the importance of the experiment for special relativity...

  • Fresnel equations
    Fresnel equations
    The Fresnel equations , deduced by Augustin-Jean Fresnel , describe the behaviour of light when moving between media of differing refractive indices...

  • Fresnel diffraction
    Fresnel diffraction
    In optics, the Fresnel diffraction equation for near-field diffraction, is an approximation of Kirchhoff-Fresnel diffraction that can be applied to the propagation of waves in the near field....

  • Fresnel drag
    Aether drag hypothesis
    In the 19th century, the theory of the luminiferous aether as the hypothetical medium for the propagation of light was widely discussed. An important part of this discussion was the question concerning the state of motion of Earth with respect to this medium. The aether drag hypothesis dealt with...

  • Fresnel imager
    Fresnel Imager
    A Fresnel imager is a proposed ultra-lightweight design for a space telescope that uses a Fresnel array as primary optics instead of a typical lens. It focuses light with a thin opaque foil sheet punched with specially shaped holes, thus focusing light on a certain point by using the phenomenon of...

  • Fresnel integral
    Fresnel integral
    250px|thumb|S and C The maximum of C is about 0.977451424. If πt²/2 were used instead of t², then the image would be scaled vertically and horizontally ....

  • Fresnel lantern
    Fresnel lantern
    A Fresnel lantern is a common lantern used in theatre, which employs a Fresnel lens to wash light over an area of the stage. The lens produces a wider, soft-edged beam of light, which is commonly used for back light and top light....

  • Fresnel lens
    Fresnel lens
    A Fresnel lens is a type of lens originally developed by French physicist Augustin-Jean Fresnel for lighthouses.The design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional design...

  • Fresnel number
    Fresnel number
    The Fresnel number F, named after the physicist Augustin-Jean Fresnel, is a dimensionless number occurring in optics, in particular in diffraction theory....

  • Fresnel rhomb
    Fresnel rhomb
    A Fresnel rhomb is a prism-like device designed in 1817 by Augustin-Jean Fresnel for changing the polarization of light waves to be circularly polarized. Though the result is similar to that of using a wave plate, the rhomb does not depend on birefringent properties of the material...

  • Fresnel zone
    Fresnel zone
    In optics and radio communications , a Fresnel zone , named for physicist Augustin-Jean Fresnel, is one of a number of concentric ellipsoids which define volumes in the radiation pattern of a circular aperture...

  • Fresnel zone plate
    Zone plate
    A zone plate is a device used to focus light or other things exhibiting wave character. Unlike lenses or curved mirrors however, zone plates use diffraction instead of refraction or reflection. Based on analysis by Augustin-Jean Fresnel, they are sometimes called Fresnel zone plates in his honor...

  • Huygens-Fresnel principle
    Huygens-Fresnel principle
    The Huygens–Fresnel principle is a method of analysis applied to problems of wave propagation both in the far-field limit and in near-field diffraction.-History:...

  • Compact Linear Fresnel Reflector
    Compact Linear Fresnel Reflector
    A compact linear Fresnel reflector – also referred to as a concentrating linear Fresnel reflector - is a specific type of linear Fresnel reflector technology. Linear Fresnel reflectors use long, thin segments of mirrors to focus sunlight onto a fixed absorber located at a common focal point of...


Further reading

  • Elton, Julia (July 2009) "A Light to Lighten our Darkness: Lighthouse Optics and the Later Development of Fresnel's Revolutionary Refracting Lens 1780–1900" International Journal for the History of Engineering & Technology 79(2): pp. 183–244, 10.1179/175812109X449612
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